Testing Strategy for Web Apps
Follow the testing pyramid: many unit tests, some integration tests, few end-to-end tests. Each layer catches different types of bugs.
Unit Tests
Test individual functions and components in isolation. Mock external dependencies. These should run in milliseconds and cover edge cases.
Integration Tests
Test how modules work together. Hit real databases (use test containers). Verify API contracts. These catch wiring bugs that unit tests miss.
End-to-End Tests
Test critical user flows in a real browser. Keep these minimal — they’re slow and flaky. Focus on signup, login, and core business flows.